12 May 2015 X-ray-induced electron cascades in dielectrics modeled with XCASCADE code: effect of impact ionization cross sections
Author Affiliations +
Abstract
Characterization of a free-electron laser (FEL) pulse can be done with a pump–probe scheme, using an FEL pump and a visible light probe on an optically transparent solid-state target. With such experimental scheme, pulse duration can be monitored on a shot-to-shot basis. It relies on the changes in optical properties induced by the FEL excitation of electrons. Here we analyze effects of different cross sections used in the modeling of electron kinetics. XCASCADE, a Monte Carlo toolkit for modeling x-ray-induced electron cascades (N. Medvedev, Appl. Phys. B 118 (2015) 417), is used for this purpose. Two different cross sections are compared: atomic BEB model vs complex-dielectric function formalism that accounts for collective effects in solids. It is shown that for photon and electron energies above a few tens of eV, the both models coincide very closely. For lower energies in the VUV regime, the difference in the cross sections become more significant, nevertheless producing qualitatively similar electron kinetics and increase in the density of excited electrons.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Nikita A. Medvedev, Nikita A. Medvedev, } "X-ray-induced electron cascades in dielectrics modeled with XCASCADE code: effect of impact ionization cross sections", Proc. SPIE 9511, Damage to VUV, EUV, and X-ray Optics V, 95110M (12 May 2015); doi: 10.1117/12.2182767; https://doi.org/10.1117/12.2182767
PROCEEDINGS
8 PAGES


SHARE
Back to Top